Oldest Water on Earth May Be Pooled in Mine 2 Miles Under Canada

Scientists may have discovered a pocket of the oldest water on Earth in a mine about two miles underground in Ontario, Canada.

The water is estimated to be about 2.6 billion years old — older than the dawn of multicellular life — leading researchers to believe that there may be other signs of ancient life buried deep under the Earth's surface.

Geoscientist Barbara Sherwood Lollar at the University of Toronto, who has been investigating deep mines around the world since the 1980s, said the pocket of water is important because it serves as a time capsule and can allow researchers to see what the environment was like at that time. What's more, sometimes microbes can survive in water sealed off within the Earth's crust, providing even more information on the time period.

"It was absolutely mind-blowing," Sherwood Lollar told OurAmazingPlanet. "These [fluids] weren't tens of millions of years old like we might have expected, or even hundreds of millions of years old. They were billions of years old."

The water was discovered when Sherwood Lollar and her team drilled holes in the mine. It isn't clear exactly how large the reservoir is.

"This is an extremely important question and one that we want to pursue in our future work," Sherwood Lollar said. "We also want to see if there are habitable reservoirs of similar age around the world."

No signs of life have been identified in the water samples, Sherwood Lollar said, but it's still a possibility.